Field of the Invention
The present invention relates to a thin film transistor array using a printing technique.
Discussion of the Background
According to the remarkable development of information technology nowadays, information is frequently transmitted and received with lap-top computers or portable information terminals. It is common knowledge that a ubiquitous society enabling information to be exchanged anywhere will be attained in the near future. In such a society, a lighter and slim information terminal is desirable. Currently, as a semiconductor material, silicon based materials are mainly employed and, as a manufacturing method, photolithography is generally used.
On the other hand, printable electronics in which an electrical component is manufactured by using a printing technique are attracting attention. By using a printing technique, the following advantages can be attained, that is, equipment cost and manufacturing cost are reduced compared to using photolithography and, since a vacuum environment and high temperature environment are not necessary, a plastic substrate can be used. In this case, as a semiconductor material, an organic semiconductor or an oxide semiconductor which are soluble in an organic solvent are often used. Thus, a semiconductor layer can be formed by a printing method. For example, according to patent literature 1, an organic semiconductor layer is formed by an inkjet method. In patent literature 2, an organic semiconductor layer is formed by a flexographic printing. Also, in patent literature 3, an organic semiconductor layer is formed by letterpress offset printing.
Patent Literature 1
    Japanese Patent Application Laid-Open Publication No. 2005-210086Patent Literature 2    Japanese Patent Application Laid-Open Publication No. 2006-63334Patent Literature 3    Japanese Patent Application Laid-Open Publication No. 2009-224665